Steve McClaren last night told his players to use Saturday' s shock FA Cup victory over Manchester United as a springboard to help secure their league survival.

The Middlesbrough manager was thrilled after seeing his side snatch two late goals through Noel Whelan and Andy Campbell to dump the Red Devils out of the FA Cup.

And the former United number two now believes the victory will spark a league revival after Boro slipped into the relegation zone last week.

Boro face Sunderland in a crucial Wear-Tees derby at the Stadium of Light tomorrow night and McClaren admitted he would think there was something wrong with his players if they did not take inspiration from the weekend's cup upset.

He said: "It honestly should not need me to tell them what they have achieved. Winning breeds confidence and they have just beaten the best.

"If they cannot take self-belief from a win like that then they never will.

"We have to take this into our league programme and that starts against Sunderland.

"We still have a tough challenge in the league and we need to pick up points.

"This is a big boost for us and we are delighted to have progressed into the next round of the Cup and this result will help the players regain their confidence."

He continued: "I was frustrated with them at half-time. We showed them far too much respect and looked as though we were just waiting to get beaten.

"We didn't pass the ball and we didn't compete. I just had to remind them that this was a fourth round cup-tie and that passion was needed.

"We showed that in the second half. It was a very uncomfortable first 45 minutes for me and I was relieved to get the players in the dressing room at half-time with the scores still level.

"We changed the personnel and the system by bringing an extra man into midfield.

"A change of attitude and players all contributed to things improving in the second half."

McClaren's men will host former Boro schemer Graeme Souness' Blackburn - who ended their Worthington Cup hopes in October - in the last 16 in three weeks' time and they will be hoping for a better turn-out by the Teesside public.

There were just over 17,000 people inside the Riverside to witness Boro's last-gasp win on Saturday, but McClaren refused to condemn the lack of support.

He said: "It was a disappointing crowd, but we have to deliver these sorts of results and performances to bring the fans back to watch us. Hopefully word of mouth will spread and we'll have a few more in for our next league match here.

"I think it was a combination of things that led to such a small crowd, including the kick-off time and the fact it was being shown live on television."

McClaren also vowed to continue in his efforts to bring Dwight Yorke to Teesside, despite the fact the striker is cup-tied after coming off the bench for the Red Devils on Saturday.

"The fact he is now cup-tied does not change things for me. We have a lot more games to play in the league than we do in the cup, so there is no change in my wish to sign him."